The Background art and a mathematical justification for the maintenance of pressure in saving carbonation has been presented in said parent application. Further experimentation by the inventor on this subject since the filing of said parent application has provided new information, as follows:
(1) When the beverage is pressurized by the introduction of air which comes in contact with the beverage in the container, as the pressure is increased to the optimum pressure of about 3 atm. abs. for stopping the CO.sub.2 bubbles from forming, the air can defuse into the beverage, mixing with the CO.sub.2 gas.
(2) CO2 gas can also be lost from the beverage as a result of turbulence generated when the beverage is being dispensed under pressure. While such a loss of CO.sub.2 may not become obvious when the beverage is overcharged with CO2, it can become detrimental to the taste of the drink when the beverage contains only a marginal CO.sub.2 charge.
(3) The methods found most effective in preserving carbonation in beverages are:
(a) allowing minimum empty volume in the container above the liquid to which the CO.sub.2 gas can escape from the body of the beverage, while the pressure in the two regions, (beverage and empty space above the beverage) equalizes;
(b) maintaining the beverage under pressure of about 3 atm. abs. without introducing air in direct contact with the beverage; and
(c) dispensing with least amount of agitation.